Examine source code of Sip Startpage

{
  "manifest_version": 2,
  "name": "Sip",
  "version": "1.6.2",
  "description": "A cozy new tab page with 9 beautiful color schemes, quick links, bookmark import, and extensive customization. Desktop Firefox only.",
  "author": "Bryan Gibson",
  "browser_specific_settings": {
    "gecko": {
      "id": "sip-startpage@bgibson72",
      "strict_min_version": "109.0"
    }
  },
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "content_security_policy": "script-src 'self'; style-src 'self' https://cdnjs.cloudflare.com https://fonts.googleapis.com; font-src 'self' https://cdnjs.cloudflare.com https://fonts.gstatic.com data:; img-src 'self' data: https:; default-src 'self'",
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "permissions": []
}